GM: December, annual sales slide on cars

GM's truck sales, including full-size SUVs and vans, were up 7.8 percent in December.

DETROIT -- General Motors closed out 2017 with a third consecutive monthly sales decline, as increased incentive spending couldn't overcome lower car demand and a strong performance from December 2016.

The automaker on Wednesday said U.S. sales last year were down 1.3 percent to just over 3 million vehicles, including a 3.3 percent decline to 308,539 units in December.

The sales were helped by an industry-leading 5 percent month-over-month increase in incentives, according to ALG. That compares with a 0.6 decline for the industry overall. The biggest factor likely was GM's employee pricing promotion to end the year.

"The return of GM's 'Employee Discount for Everyone' campaign resulted in the largest rise of incentive spending on a month-over-month basis among major OEMs," said Eric Lyman, ALG's chief industry analyst.

U.S. market share: 19.2% in Dec. 2017, up from 18.9% in Dec. 2016; 17.4% for all of 2017, up from 17.3% in 2016.

Incentives: $5,007, up 4.4% from a year earlier and a 5% increase from November, according to ALG. That's forecast to be 13% of its average transaction price per unit.

Average transaction price:$38,603 per vehicle, up 1% from a year earlier, according to ALG.

Fleet mix: 17.5%, down 4.1 percentage points from a year ago; 19.2% in 2017, down 0.3 percentage points.

Inventory: 63-day supply to end December, or 752,554 vehicles. That's down from 83 days, or 819,327 vehicles, a month ago. GM overdelivered on its goal of ending the year with about a 70-day supply, below the 843,700 vehicles it had on hand at the end of 2016.

Quote: "We are starting 2018 with very lean inventories for such a strong industry, and we see more room to grow because Chevrolet, Buick and GMC will have a full year of sales of their all-new crossovers, and we are going to launch the industry's best full-size pickups," said Kurt McNeil, GM's U.S. vice president of sales operations.

Did you know? GM last year set new annual sales records for pickups (948,909 units), crossovers (965,090) and electric vehicles (43,669 units) as well as average transaction price (more than $35,400).